Lubrication system



J. A. STAHN 2,482,806

LUBICATION SYSTEM Sept. 27, 1949.

Filed Jan. 5, 1948 INVENToR. JAY/W55 AZ 570///V Patented Sept. 27, 1949 UNITED STATES PATENT OFFICE (Granted under the act of March 3, 188e, as amended April so, 192s; 37o o. G. 757) 2 Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes without payment to me of any royalty thereon.

This invention relates to improvements in deaerator valves and more particularly to de-aerator vent valves for use in high altitude aircraft lubrieating systems, and has for an object the provision of de-aerator valve means for normally providing a restricted vent means for a de-aerating chamber having thermostatically responsive relief valve means for increasing the area of the vent means incident to a predetermined decrease in temperature of the iluid being vented.

A further object is the provision of improved deaerating valve means having a predetermined metered ow therethrough and yieldable pressure responsive means for providing an increase ow around the metering valve means at low temperatures, to prevent stoppage of the metered f flow by the congealment of the fluid in the metering openings at low temperatures.

A further object is the provision of de-aerating valve means having a valve seat and spring loaded low temperature responsive venting valve means formed with a predetermined venting area for passing a de-aerated iluid therethrough, in which the temperature responsive means displaces the venting valve from its seat when the temperature of the fluid passing said valve is below a predetermined low temperature, to thereby increase the venting area.

A still further object is the provision of improved de-aerating valve venting means having spring loaded and temperature responsive venting valve means for offering a predetermined yieldable resistance to flow of the fluid to be aerated therethrough at normal temperatures and viscosity and providing a predetermined increased ,ow at low temperatures when the Viscosity of the lluid is greater.

A further object is the provision of a fluid circulation system having a de-aerating pressure relief valve device including a vented iiuid metering valve member for controlling and predetermining the passage of the de-aerated fluid therethrough in a predetermined ratio to the temperature, viscosity, and pressure of the uid being circulated.

A further object is the provision of a de-aerator having a vented displaceable metering valve which provides a large area for the flow of deaerated air and oil therethrough when the engine is started, to decongeal any cold oil in the metering holes of the displaceable metering valve that would have a tendency to clog with congealed oil at low temperatures, including thermostatic means for unseating the valve at low temperatures to permit the free flow and seating the venting valve as the air and oil vapors become hotter due to an increase in the oil temperature, to thereby reduce or eliminate the free flow of the de-aerated fluid except the fluid llowing through the metering holes in the valve means.

A further object includes the provision of yieldable seating means for yieldably holding the meter valve means on its seat so that in the event of clogging of the metering valve means the metering valve means yields to permit air and oil vapors to now around the metering valve means to heat the same and clear the metering valve apertures. e Other objects and advantages of my invention will become apparent from the following description, taken in connection with the accompanying drawings, in which like reference character-s refer to like parts in the several -gures.

Fig. 1 is a diagrammatic view of a closed lubricating system for an internal combustion engine, incorporating my improvedY de-aerating valve means.

Fig. 2 is an enlarged longitudinal sectional view taken through my improved valve means showing the same in normal or closed position.

Fig. 3 is a side elevation of my de-aerator valve with the lower portion thereof broken away and shown in section. The valve being illustrated in retracted position from its valve seat by the cold temperature responsive device, illustrating the position of the valve when the oil is cold.

Fig. 4 is a view similar to Fig. 3, also showing the valve in its bypassing position, illustrating the position of the valve when the oil viscosity is heavy or when the vent openings are clogged.

Referring more particularly'to Fig. 1, a closed lubricating or oil circulation system for an internal combustion engine is illustrated, somewhat analogous to the closed oil lubricating system illustrated in Fig. 1 of United States Patent 2,024,- 336 to G. S. Cavanaugh, patented December 17, 1935, the reference numeral I designating an internal combustion engine preferably of the dry sump type, such as an aircraft engine. Lubricating oil after being circulated through the engine in the usual manner is withdrawn from the sump 2 by a scavenging oil pump 3 and delivered through a conduit 4 to a conventional de-aerating device or chamber 5. The oil after passing through suitable de-aerating baffles or other similar flow Vretarding means within the de-aerating chamber 5 is withdrawn from the lower portion of the de-aerating chamber through a conduit 6 by the main engine pressure pump 'I and is again delivered to the engine under pressure through a conduit 8, and is distributed to the engine bearings in the conventional manner. An oil coole-r 9 of conventional construction is interposed in the conduit 6 for cooling and controlling the temperature of the o il that is returned to the engine through conduits 6 and 8.

An eductor nozzle I0, also of conventional con.- struction, is interposed in the cil return conduit 6 between the oil cooler 9 and the main engine pressure pump 'I and is provided with an oil supply line II leading from the lower portion of a main oil reservoir l2. The eductor I8, through its connected supply line II, supplies fresh oil from the reservoir I2 to the conduit 6 to replace oil that is used up during the operation of the engine I.

My improved de-aerator valve device is indicated at I3 and is mounted over the port I4 (Fig. 2) formed in the top I5 of the casing of the deaerator device 5, and is securely retained in position over the opening I4 by any conventional fastening means, such as a retaining ring I6 secured in place by screw fasteners I'I and sealed with a gasket I8. The top portion of my deaerator Valve casing I3 is formed with a reduced tubular venting extension 20 having a tapped bore 2| extending therethrough. A venting conduit 22 -is threadably received in the bore 2l with its opposite end secured in communication with the interior of the mail oil reservoir I2, above the liquid level therein.

Referring particularly to Figs. 2 to 4 the deacrator valve casing I3 is preferably -a twopart cylindrical casing, having -a base ange 23 and inwardly extending Valve seat 24. The lower section .of the casing 3 is for-med vwi-tlfi a counterbored end 25 forming an annular stop shoulder 25, and is threaded to receive the top closure portion 2 having the .central vent opening 2| therethrough. The periphery of the closure or cap 2 y'I is also threaded to 'be received by the threads in the counter-bored portion 25 of the casing.

A supporting plate 26 is secured in the counterbored portion, and is seated against the annular shoulder 26 by the lower edge of the cap 24 when the same is securelyscrewedin place. An annular sealing gasket 29 is provided, preferably between the cap 2 and the plate `28, retaining the plate its seat 26. Carried by 'the `plate 28 axially within the casing I3, is a cold temperature responsive `valve actuator 30, having an actuating stem Si which extends 4axially -within fthe casing and projects concentrica-lly through the annular opening in the end of the casing that forms the valve of seat 24.

'The thermostatic device 3l) may -be a conventional ty-pe of gas--lled bellows of the Sylphon type secured at one end within the casing with the valve actuating stem connected and projecting through the suitable opening in the bel- Ylows casing. The supporting plate 2K8 is formed with anannular ring of vent 01 12W- Dass apertures 'S-8a to allow fluid or gas to pass through the plate 28. A perforated disk or venting valve 32 vis'concentrically and slidably carried on the valvestem 3fI andis formed with a central cup-shaped recess 33 to receive -a collar or nut I3 Iafi'xed on the stem 3-I. The valve disk 32 is relatively thin and light, having an annular angularly v ent rim arranged for seating engagement with the valve Seat24. The valve disk 3 2 is formed la pluralityof small-venting openings'therethrough, providing a predetermined venting area when the valve is seated. A coil compression spring 36 surrounds the valve stem 3I with its opposite ends engaging the lower face of the thermostatic actuator casing I3 and the upper face of the valve disk 552, normally retaining the valve disk 32 seated on its Seat 24`zduring normal Dpltting conditions of the engine when the oil is warm. This normal position of the valve 32 restricts, to a predetermined extent, the flow of air or gaseous fluid that has been removed from the oil by the de-aerator 5 and returned to the oil reservoir I2 through the .Conduit 22.

When the oil is cold its viscosity is somewhat higher and tends to cloud the small openings 35 and the disk 32. The temperature responsive device 3] withdraws the stem 3|, causing the nut or collar 3l@ fixed thereon to engage the base of the recess 33 and lift the valve 32 off of its seat, to a position such as shown in Fig. v3. The valve reina-ins in this position permitting circulation o f a portion of the oil or fluid to pass the valve 32 and `to pass the temperature responsive device 36 until the oil is sufliciently warmed by the engine to cause the temperature responsive device to lower the valve 3 2 to its normal operating position on its seat 24, as sho-wn in Fig. 2. Thewarm oil readily clears any thick or congealed oil that was formerly present in the perforation 35 of the valve, and as the de-aeration of the warm and thinner oil takes place the deaerated gases pass readily through the valve perforations and out through the vent pipe 22. A

Should the oil become excessively viscous during use, or should the periorations 35 in the disk valve become clogged with dirt, or should the oil pressure `in the d e-aerator casing 5 rise ybeyond a predetermined deg-ree due to retarded flow through the oil cooler, even though the temperature Y'of the oil is above the lpw temperature required to open the valve by the temperature respofrisivendevice 30, the coil spring 36 will readily yield to permit the valve 32 to slide to its venting position as shown in Fig, 4 and the excessive oil pressure will `be safely vented through the venting'pipe 22 and passed bac-k lto the main oil reservoir -I-2. The tension of the coil spring 35 is predetermined however s o that the valve will be maintained on its seat, if not unseated by the temperature responsive `device 3p due to th'e -liw temperature of the oil, until the oil pressure 15e,- tween the scavenging pump 3 andtfheoil cooler@ exceeds the predetermined vsa-feoperating pressure. When -this pressure is reached the spring 36 yields and `the valve '32 lifts to reduce the pressurre. .The velocity and temperature of the'iluid or oil passing the valve 32 Amay then assist clearing the perforations y35 of congealed oil and dirt. Y v' u K Y" `While the drawings illustrate as irnple radaptatios of -my invention it lis @wipes th t'prlrjirlior Changes moy loo .made .in tho .ooosimoi .1.1 Jill/1S- traoo Without departing .from .the .spirit .of the invention as donod'by .the oppoooedolains In the foregoing dosoriotlioa .my ororiiioe hoo Poo# dosorilood .1.1.1 commotion with internal `oombusiion airoraft oef-ino of the 4olrv .oil Sump lime, but it .is Within the .Sooloo and Dur-Mirow `of .mv invonton as olaimed ,to .uso :my ,imo'royoo flo-@order vont rali/.o insumo-.notion wiooothorisblooontoinoulation .Systems such .as in oooiimotion with .o closed .0.1.1 system for .eas turbine engines ifo-r .oir-- craft.

llolaim;

1. In combination with a closed lubrication circulation system for aircraft internal combustion engines having a sump, a reservoir, a de-aerating chamber, pump and conduit means connected between the sump and the de-aerating chamber forv pumping fluid from said sump to said de-aerating chamber, recirculation conduit means between the de-aerating chamber and the engine for returning at least a portion of the iiuid received by said de-aerating chamber to said engine,A a return conduit connected between the de-aerating charnber and the reservoir for returning uid from said de-aerator to the reservoir; of a fluid metering valve means in said last-mentioned conduit having a Valve seat and metering valve means normally engaging said seat, and low temperature responsive valve actuating means for unseating the said metering Valve means at predetermined low temperature to by-pass the uid in the return conduit around the metering valve means when the temperature of the uid is below said predetermined low temperature.

2. In combination with a de-aerating system for de-aerating the lubrication system of an aircraft internal combustion engine having a sump, a reservoir, pump and conduit means connected to the sump for pumping lubricant from the sump, a de-aerating chamber connected to the pump for receiving fluid pumped thereby and deaerating the same, a fluid conduit connected between said de-aerating chamber and the engine for returning at least a portion of the lubricant, that is pumped by the pump, to the engine for recirculation, and a fluid return conduit between the upper portion of the de-aerating chamber and the reservoir; of a de-aerating Valve device interposed in said fluid return conduit comprising a casing having a metering Valve seat formed there- Valve from said de-aerating chamber to said reser- Voir part when the fluid temperature is below a predetermined temperature and when the fluid pressure in the de-aerating chamber exceeds a predetermined pressure regardless of the temperature of the uid.

JAMES A. STAI-IN.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,927,036 Johnson f Sept. 19, 1933 2,300,825 Bloom Nov. 3, 1942 2,333,993 Frailng NOV. 9, 1943 '2,379,109 Shaw June 26, 1945` 2,400,911 Booth May 28, 1946 2,421,713 Porter June 3, 1947 FOREIGN PATENTS Number Country Date 461,707 Great Britain Feb. 23, 1927 

